(Adapted from the Applicant's Abstract) While past efforts on the part of researchers and professionals have led to more effective treatments of the complications associated with SCD and little is known about the social epidemiology of SCD (that is, critical and accessible data on the physical, psychological and social aspects of SCD). Questions about the access, differential outcomes, and use of health and social services of persons with SCD, remain largely unanswered. To begin to add new knowledge to the understanding of the lives of persons with SCD, and to provide a state-level sociological counterpart to the CSSCD, the UAB Comprehensive SCD Center proposes to establish, maintain and use, a registry for persons with SCD in Alabama. Specific Aim 1: To develop and implement a SCD client registry for the purpose of maintaining key epidemiologic, socio-demographic, health care and social data on persons with SCD that will be used for planning clinical care, case management, advocacy, and research. Specific Aim 2: To use the first wave core and supplemental data from the registry to: (a) describe the frequency and demographics of SCD in Alabama; (b) document the prevalence of (i) self-reported illness experiences, and (ii) health and human services access and use, of persons with SCD in Alabama; and (c) to test research hypotheses identifying factors associated with the differential service experiences, gaps and barriers in the access to, and use of, the existing human and health care service systems for persons with SCD in Alabama. These hypotheses are: 2.1 Persons with SCD (or their parental caretakers) living in urban counties of Alabama will be more likely to report greater knowledge of available services (perceived availability), greater access to (perceived access), use of, and satisfaction with these services, than rural persons with SCD. 2.2. Children and adolescents with SCD (or their primary caretakers) living in Alabama will be more likely to have reports of greater knowledge of available services (perceived availability), greater access to (perceived access), use of, and satisfaction with these services, than adults with SCD living in Alabama. Methodology; Based on Specific Aim 1: The development of a SCD Registry will involve two phases: planning and development (months 1 to 11 of year 01) and implementation (Years 02 through 03 and every two years thereafter). Based on Specific Aim 2: Beginning in year 04, wave one data from the registry will be organized and linked with state-level data. Using epidemiologic methods client characteristics, service use, access and satisfaction patterns will be documented; using bivariate and multi-variable statistics and the framework of the Anderson and Aday Access model as a guide, hypothesized relationships will be tested and conclusions will be drawn.